Motor coil configuration and motor having same

Abstract

An electric machine configured to transmit electrical power (e.g., by conversion between electrical power and mechanical power) includes a slot in which a coil is disposed. The slots may be stator slots having a trapezoidal cross-sectional shape. The coil may have a plurality of turns, the cross-section of which also includes a trapezoidal shape. The turns may be stacked on each other in a radial direction between a proximal end and a distal end of the stator slot, each turn of the coil having a different cross-sectional area and a different radial height relative to an adjacent turn of the coil. Additionally and / or alternatively, each turn of the coil has a reduced radial height relative to a turn of the coil located radially outside of each turn of the coil except for the turns of the coil located at the distal end of the stator slot.

Description

Technical Field

[0001] The present disclosure relates to electrical machines, such as generators and motors. Background Art

[0002] Electric motors are used in various applications, such as automotive applications, aerospace applications, industrial applications, etc. Electric motors generally include a rotor and a stator, and can take various forms, including electric motors or generators. Electric motors are generally used to convert electrical energy into mechanical energy, or mechanical energy into electrical energy.

[0003] Regardless of the type, electric motors include several components, including a rotor and a stator. Electric motors also include field devices, such as coils that typically include multiple turns of conductive material. Improvements to the configuration of the coils and the operation of electric motors would be useful in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] A complete and enabling disclosure of the presently described technology, including the best mode thereof, to one of ordinary skill in the art is set forth in the specification with reference to the accompanying drawings, in which:

[0005] Figure 1 A is an embodiment of a motor according to an exemplary aspect of the present disclosure.

[0006] Figure 1 B is an embodiment of a motor according to an exemplary aspect of the present disclosure.

[0007] Figure 2 is an embodiment of a motor according to another exemplary embodiment of the present disclosure.

[0008] Figure 3 is an embodiment of an electric machine having coils in a concentrated winding arrangement according to an exemplary embodiment of the present disclosure.

[0009] Figure 4 is an embodiment of an electric machine having coils in a distributed winding arrangement according to another exemplary embodiment of the present disclosure.

[0010] Figure 5 is a depiction of multiple turns of a coil positioned in stator slots according to another exemplary embodiment of the present disclosure.

[0011] Figure 6 is a depiction of a plurality of end turns of a coil according to another exemplary embodiment of the present disclosure.

[0012] Figure 7 is a depiction of multiple turns of a coil positioned in stator slots according to another exemplary embodiment of the present disclosure.

[0013] Figure 8is a graphical representation of a configuration of a coil according to another exemplary embodiment of the present disclosure relative to prior art devices.

[0014] Fig. 9 is a graphical representation of a configuration of a coil according to another exemplary embodiment of the present disclosure relative to prior art devices.

[0015] Fig.10 is a depiction of multiple turns of a coil positioned in stator slots according to another exemplary embodiment of the present disclosure.

[0016] Fig.11 is a depiction of coils in a stator according to another exemplary embodiment of the present disclosure.

[0017] Fig.12 is a depiction of a vehicle including an electric machine according to another exemplary embodiment of the present disclosure.

[0018] Fig.13 is a depiction of a computing system according to another exemplary embodiment of the present disclosure.

[0019] Fig.14A is a depiction of a method of constructing an electric machine according to another exemplary embodiment of the present disclosure.

[0020] Fig. 14B is a depiction of a method of constructing an electric machine according to another exemplary embodiment of the present disclosure.

[0021] Fig.15 is a depiction of multiple turns of a coil positioned in stator slots according to another exemplary embodiment of the present disclosure.

[0022] Fig.16 is a depiction of multiple turns of multiple coils positioned in stator slots according to another exemplary embodiment of the present disclosure.

[0023] Fig.17A is a depiction of a stator segment according to another exemplary embodiment of the present disclosure.

[0024] Fig. 17B is a depiction of a stator segment according to another exemplary embodiment of the present disclosure.

[0025] Fig. 17C is a depiction of a stator segment according to another exemplary embodiment of the present disclosure.

[0026] Fig.17D is a depiction of a stator segment according to another exemplary embodiment of the present disclosure.

[0027] Fig.18A portion of a stator according to another exemplary embodiment of the present disclosure is shown. The stator is configured to be placed radially inside a rotor, for example, Figure 1 B's motor. DETAILED DESCRIPTION

[0028] Reference will now be made in detail to the present embodiments of the present disclosure, one or more examples of which are shown in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the present disclosure.

[0029] The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. Furthermore, unless expressly stated otherwise, all embodiments described herein should be considered exemplary.

[0030] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0031] The term "gas turbine engine" refers to an engine having a turbine as all or part of its power source. Example gas turbine engines include gas turbine engines, turboprop engines, turbojets, turboshaft engines, etc., as well as hybrid electric versions of one or more of these engines.

[0032] The terms "axial" and "axially" refer to directions and orientations extending substantially parallel to a reference axis. Additionally, the terms "radial" and "radially" refer to directions and orientations extending substantially perpendicular to a reference axis. Additionally, as used herein, the terms "circumferential" and "circumferentially" refer to directions and orientations extending in an arc around a reference axis.

[0033] Unless otherwise specified herein, the terms "coupled," "fixed," "attached to," and the like refer to both direct coupling, fixing, or attachment as well as indirect coupling, fixing, or attachment through one or more intermediate components or features.

[0034] As used herein, the terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another, and are not intended to indicate the position or importance of each component.

[0035] The present disclosure generally relates to electric machines having improved performance based on a unique coil configuration, and in particular, a unique turn configuration disposed in slots of the electric machine. The coil includes a plurality of turns stacked on top of each other in a radial direction between a proximal end and a distal end of a stator slot, each turn of the coil having a different cross-sectional area and a different radial height relative to adjacent turns of the coil. The turns may be solid conductors, wherein a single turn occupies a given radial space. In addition to the turns of the coil located at the distal ends of the stator slots, the coil may alternatively and / or additionally have each turn of the coil including a reduced radial height relative to turns of the coil located radially outside of each turn of the coil. An unexpected relationship of the turns was discovered, namely, for each of the plurality of turns, In the equation, r nt is the limiting ratio, h t is the coil n th Height of turns, h c is the height of the coil and n is the coil number being evaluated.

[0036] Referring now to the drawings, wherein like numerals refer to like elements throughout, Figure 1 A is a perspective view of an embodiment of an electric machine 10 . The electric machine 10 includes a stator 12 and a rotor 14 , both of which are concentrically aligned about a central longitudinal axis 16 of the electric machine 10 . Figure 1 The rotor 14 of A is positioned radially inside the stator 12 . Figure 1 B depicts Figure 1 A variation of the motor 10. Although Figure 1 The motor of A includes a rotor 14 positioned radially inside a stator 12, but Figure 1 Embodiment B includes a rotor 14 positioned radially outside of a stator 12. Figure 1 The same as the embodiment of A, Figure 1 The stator 12 and rotor 14 of the embodiment in B are concentrically aligned about a central longitudinal axis 16 .

[0037] Whether Figure 1 A or Figure 1In the embodiment of B, the stator 12 and the rotor 14 are electromagnetically coupled to each other during the operation of the motor 10, and are generally used together as an electromechanical energy converter. The rotor 14 is configured to rotate relative to the stator 12 during the operation of the motor 10. The motor 10 can be an electric motor, wherein the rotor 14 rotates relative to the stator 12 to convert electrical energy into mechanical energy. Alternatively, the motor can be a generator, wherein the relative rotation between the rotor 14 and the stator 12 converts mechanical energy into electrical energy. Whether operating as a generator or an electric motor, it is conceivable that the motor 10 can be coupled to various vehicles and machines, including, for example, aircraft, land vehicles (such as cars and trucks), locomotives and ships. In a specific example, the motor 10 can be coupled to a gas turbine engine used as a power plant for an aircraft. It is conceivable that the motor 10 in this embodiment can be coupled to a shaft (e.g., a low-pressure shaft, an intermediate-pressure shaft, or a high-pressure shaft) of a gas turbine engine to serve as a motor and / or a generator.

[0038] The motor 10 of the embodiments described herein may be any type of rotating motor, such as, but not limited to, a synchronous motor, a multi-phase motor, a motor with concentrated windings, a motor with distributed windings, a reluctance motor, an induction motor, a wound field motor, a salient pole motor, an interior permanent magnet (IPM) motor, a motor with permanent magnets arranged differently from an IPM motor (e.g., a surface PM motor, etc.), etc. In addition, the motor 10 of the embodiments described herein may be a permanent magnet motor, a wound field synchronous motor, an induction (asynchronous) motor, a synchronous reluctance motor, and a switched reluctance motor.

[0039] The stator 12 extends a certain length along the central longitudinal axis 16. The stator 12 includes a stator core 18 having a central opening 20 extending along the central longitudinal axis 16. The rotor 14 extends a certain length along the central longitudinal axis 16 and is generally positioned within the central opening 20 and radially inward of the stator 12. The rotor 14 includes a rotor core 24 that can be coupled to a shaft 22. The shaft 22 is configured to rotate relative to the stator core 18 about the central longitudinal axis 16 with the rotor core 24. The rotor core 24 can be mounted to the shaft 22 so that the rotor core 24 is configured to rotate about the central longitudinal axis 16 with the shaft 22. In an alternative embodiment, the rotor 14 can be configured to extend around the stator 12 so that the rotor assembly is configured to rotate radially outside the stator 12 and around the stator 12.

[0040] Figure 21 is a cross-sectional view of an embodiment of an electric machine 10 in which a stator 12 and a rotor 14 extend in a circumferential direction CD about a central longitudinal axis 16. The stator 12 is offset from the rotor 14 in a radial direction RD, particularly in a radially outward direction, from the central longitudinal axis 16. In the illustrated embodiment, the stator core 18 includes a stator base 28 and a plurality of stator teeth 30 extending radially between the stator base 28 and ends 32 of the stator teeth 30. In the illustrated embodiment of the stator 12, the stator teeth 30 extend radially inward from the stator base 28.

[0041] like Figure 2 As shown, the stator teeth 30 are radially arranged about the central longitudinal axis 16 so that the stator teeth 30 are circumferentially spaced apart from each other. The stator core 18 includes stator slots 34, which are positioned between adjacent stator teeth 30 and radially inward from the stator base 28 toward the stator teeth. In some alternative embodiments, the ends 32 of adjacent stator teeth 30 are connected together, or include portions extending toward each other so as to form an opening that is smaller in size than the width of the slot 34. It is envisioned that the cross-sectional shape of the stator slots is trapezoidal, the details of which will be better explained in further embodiments below. However, other embodiments may include stator slots 34 that are rectangular in shape. In addition, as will be further described below, in some embodiments, the stator can be a segmented stator.

[0042] The stator 12 also includes field coils 36, the windings of which are disposed in the stator slots 34 between the stator teeth 30. The field coils can be configured such that the windings extend between opposite axial ends of the stator 12 and are wound around respective stator teeth 30, thereby placing portions of the windings in individual stator slots 34. Each coil 36 can be or represent any number of phases, such as, but not limited to, a single phase or three phases. The windings of the field coils 36 can be configured in a variety of arrangements, including a concentrated winding arrangement (an example of which is shown in FIG. 1 ). Figure 3 ) and a distributed winding arrangement (an example of which is shown in Figure 4 Therefore, the description herein is applicable to various winding arrangements. Figure 3 The coils 36 a - 36 f are shown wound around respective stator teeth 30 a - 30 f such that the windings of the respective coils 36 a - 36 f are located in stator slots 34 that are located on opposite sides of a given stator tooth 30 . Figure 4 The coils 36 a - 36 f are shown wound around adjacent stator teeth 30 such that the respective coils 36 a - 36 f span across but do not extend into the stator slots 34 located between adjacent stator teeth 30 .

[0043] Return to Figure 2In the embodiment shown in FIG. 1 , the coil 36 can be made using any number of manufacturing techniques and can be made from a variety of conductive materials. In one form, the coil 36 is made from a variety of metals or metal alloys, including copper, aluminum, or other alternative metal alloys (e.g., brass alloys, iron alloys, etc.). The metal or metal alloy material can have a variety of metal conductivity values. In one form, the conductivity of the material of the coil 36 is 0.3-1.0 pu of International Annealed Copper Standard (IACS) copper at room temperature. As is well known, 1 pu = 5.8001 x 10 7 Siemens / meter. Furthermore, coil 36 may be manufactured using any number of techniques, including additive manufacturing, casting, and machining.

[0044] The stator core 18 may include any number of stator teeth 30 and any number of stator slots 34. In the illustrated embodiment of the stator 12, the stator core 18 includes twenty-four stator teeth 30 and twenty-four stator slots 34. The stator core 18 may include any number of coils 36 and may be configured to operate with any number of phases.

[0045] The stator 12 may include ground insulation 40 positioned within the stator slots 34 to electrically isolate the coils 36 from the stator core 18. Other insulation may also be used to separate the turns of the coils 36, as will be discussed and illustrated below in further additional and / or alternative embodiments.

[0046] The rotor core 24 includes a body 42 that extends axially along the central longitudinal axis 16 and is configured to rotate relative to the stator 12 about the central longitudinal axis 16. In the illustrated embodiment of the rotor 14, the body 42 includes a rotor base 44, a plurality of magnetic segments 46 extending in a radial direction from the rotor base 44, and a plurality of non-magnetic segments 48 extending in a radial direction from the rotor base 44. Although the magnetic segments 46 and the non-magnetic segments 48 extend radially inward from the rotor base 44 in the illustrated embodiment, in some alternative embodiments, the segments 46 and 48 may extend radially inward from the rotor base 44.

[0047] The magnetic segments 46 and the non-magnetic segments 48 are arranged in an alternating pattern in the circumferential direction such that the magnetic segments 46 are spaced apart from one another with the non-magnetic segments 48 extending between adjacent magnetic segments 46. In the illustrated embodiment of the rotor 14, the rotor 14 may be considered a toothed rotor with the magnetic segments 46 defining rotor teeth of the rotor core 24.

[0048] The air gap extends between the circumference of the rotor core 24 and the radial inner surface 26 of the stator core 18. In the illustrated embodiment, the rotor base 44 of the rotor core body 42 includes a radial inner surface 50 that defines a central opening 52 of the rotor core 24. The rotor base 44 may include one or more mortises (not shown) configured to receive corresponding tenons (not shown) of the shaft 22 therein for mounting the rotor core body 42 to the shaft 22. Other arrangements for mounting the rotor core body 42 to the shaft 22 may be provided in addition to or as an alternative to the mortises and tenons.

[0049] The body 42 of the rotor core 24 may be formed from one or more stacks of a plurality of laminations. As an alternative to using one or more stacks of laminations, the rotor core body 42 may be formed as a single piece of material. The rotor base 44 of the rotor core body 42 may be formed integrally with the magnetic segments 46 and / or the non-magnetic segments 48. For example, when the body 42 of the rotor core 24 is formed from a stack of laminations, the rotor base 44 of each lamination or layer within the stack may be formed integrally with the magnetic segments 46 and / or the non-magnetic segments 48 of the laminations. In addition, for example, in an embodiment in which the rotor core body 42 is formed as a single piece of material, the rotor base 44 is a single piece of material integrally formed with all the magnetic segments 46 and non-magnetic segments 48 of the rotor core 24. In the illustrated embodiment of the rotor 14, the magnetic segments are magnetically connected to the rotor base 44, so that the rotor 14 is a toothed rotor. In other words, the rotor base 44 carries the magnetic flux. The toothed rotor structure of rotor 14, whether constructed from a stack of laminations or a single piece of material, distinguishes rotor 14 from a "segmented" rotor 14, which includes a rotor core having magnetic segments that are magnetically isolated or segmented from a rotor base and each other. As in the illustrated embodiment of electric machine 10, stator 12 and / or rotor 14 may or may not include permanent magnets. In some alternative embodiments, rotor 14 is a segmented rotor.

[0050] The rotor core 24 may include any number of magnetic segments 46 and / or non-magnetic segments 48. For example, the rotor core 24 may include any number of rotor teeth 30. The rotor core 24 may include the same number of rotor teeth 30 as the stator core 18 includes. Alternatively, the stator core 18 may include a greater or lesser number of stator teeth 30 than the number of rotor teeth 30 included in the rotor core 24. In the illustrated embodiment of the electric machine 10, the rotor core 24 includes fourteen rotor teeth 30, such that the illustrated embodiment of the electric machine 10 includes a greater number of stator teeth 30 than the number of rotor teeth 30.

[0051] Now go to Figure 5 and Figure 6 , an embodiment of the stator 12 , stator slots 34 , and coils 36 are shown. Figure 5, the stator slot 34 is shown to have a trapezoidal cross-sectional shape. The coil 36 also has a trapezoidal cross-sectional shape and is disposed in the stator slot 34. The turns of the coil 36 have specific shapes and relative sizes, which will be further described below. In one form, the trapezoidal shape of the coil 36 is complementary to the trapezoidal shape of the stator slot 34. The relationship between the turn shape and relative size of the coil 36 can unexpectedly reduce the ohmic losses of the winding of the coil 36, thereby improving the efficiency of the motor 10. Unlike the constant height or constant area cross-sectional turns of the coil 36 used in the prior art devices, it has been found that different relationships can improve efficiency by considering losses including skin effect, circulating current and proximity losses. However, the area in which the present application achieves favorable results can be limited by several factors including the operating frequency. The numerical ranges of various factors affecting performance will be further described below.

[0052] It should be understood that although Figure 5 In the example of the stator slots 34 and the coils 36 have a trapezoidal cross-sectional shape, but in some embodiments the long and short sides of the trapezoidal cross-sectional shape may be curved. In other embodiments, the long and short sides of the trapezoidal cross-sectional shape are strictly linear segments of a typical geometric trapezoidal shape. Therefore, as used herein, the expression "trapezoidal cross-sectional shape" should be understood to include those shapes having strictly linear shapes on all sides of the trapezoid, as well as those shapes including long and short sides, one or more sides having a curved shape. The curved shape may be a circumferential arc having a radius of curvature commensurate with the radial distance from the central longitudinal axis, but other radii of curvature may also be considered.

[0053] The trapezoidal shape of the stator slot 34 includes a first end 54 and a second end 56, and a sidewall 58 extending between the first end 54 and the second end 56. Figure 5 As shown in the example of , the first end 54 is larger than the second end 56, wherein the sidewalls 58 are inclined toward each other at a taper angle 60 when the sidewalls 58 connect the first end 54 to the second end 56. The taper angle 60 is the angle formed by the sidewalls 58 relative to a radial line extending from the central longitudinal axis 16. In the case of the trapezoidal shape contemplated in some embodiments herein, the taper angle 60 causes the second end 56 to have a smaller circumference than the first end 54. In some forms, the first end 54 may be referred to as the distal end of the stator slot 34, while the second end 56 may be referred to as the proximal end of the stator slot 34. This use of the terms "distal end" and "proximal end" is intended to convey a spatial orientation relative to the rotor 14. The proximal end 56 is the end of the stator slot 34 that is close to the rotor 14, while the distal end 54 is opposite the proximal end 56 and is located at the end of the stator slot 34 that is farthest from the rotor 14. In other words, the "distal end" of the stator slot 34 is radially farthest from the rotor 14, while the "proximal end" of the stator slot 34 is radially closest to the rotor 14.

[0054] The proximal end 56 may include an opening between the stator teeth 30 that is filled with a wedge 57. The wedge 57 may be any suitable size and dimension for closing the opening between the stator teeth 30 and may be made of any suitable material. In some embodiments, the wedge 57 need not be present.

[0055] Figure 5 and Figure 6 36 is depicted as having ten turns and a gap between the coil 36 and the proximal end 56 of the stator slot 34. In some embodiments, it should be understood that the coil 36 may have more or fewer turns, thereby occupying more or less space within the stator slot 34. In some embodiments, the gap between the coil 36 and the proximal end 56 of the stator slot 34 may be absent, such that the coil 36 occupies the entire radial height between the proximal end 56 and the distal end 54 of the stator slot 34. Figure 6 is a cross-sectional view depicting an end turn of coil 36 , as shown by turn 62 . Figure 5 and Figure 6 A total of ten (10) turns 62 of the coil 36 are shown in FIG. 8 , but other embodiments may include more or fewer turns 62 . Figure 5 and Figure 6 The curvilinear nature of the sides of the trapezoidal cross-sectional shape is also depicted.

[0056] In the illustrated embodiment, the turns 62 are solid conductors that are stacked one on top of the other in a continuous sequence. In many embodiments, it is contemplated that for a given coil 36, there is only a single turn 62 at each radial position of the turn, which is different from a winding turn, which may include one or more overlapping turns at each radial position. In some forms, the turns 62 may include a continuous length of coil 36 from a turn 62 located near the proximal end 56 to a turn 62 located near the distal end 54 of the stator slot 34. The coil 36 may be produced using any suitable technique, including those described above. Thus, the turns 62 may be unitary structures, such as those that may be produced by a casting operation, an additive manufacturing operation, and / or a machine operation. In some forms, the winding may be roughly formed into an initial shape by an additive manufacturing or casting operation and then machined into a final form.

[0057] Figure 5 The arrangement shown in can be referred to as a side-by-side double-layer winding, and at least in the illustrated embodiment, includes spaces 64 between the solid conductors of the turns 62 within the stator slots 34. Examples of single-layer windings and double-layer overlapping windings can be found in the following Fig.15 and Fig.16 Note that in some embodiments, Figure 5The space 64 shown in FIG. 1 is relatively constant over the height of the coil 36. This is in contrast to some prior art coils 36 in which the turns 62 have a constant cross-sectional area. As will be further described below, in some embodiments contemplated herein, the cross-sectional area of ​​the turns 62 will have a non-constant cross-sectional area between turns 62.

[0058] Figure 5 and Figure 6 Also shown is the relationship of the radial height of each turn 62 relative to the position of the turn 62 between the proximal end 56 and the distal end 54. The turn 62 closest to the proximal end 56 has a smaller radial height and / or a smaller cross-sectional area than the turn 62 located radially farthest from the rotor 14. In some embodiments, the relationship between the turns 62 located near the proximal end 56 having a smaller radial height and / or a smaller cross-sectional area than the turns 62 located near the distal end 54 may apply to all turns 62. For example, in the illustrated embodiment, any turn 62 located radially inward relative to another turn 62 will have a smaller radial height and / or a smaller cross-sectional area. Conversely, any turn 62 located radially outward relative to another turn 62 will have a larger radial height and / or a larger cross-sectional area. In this sense, the radial height and / or cross-sectional area of ​​each turn 62 of the coil 36 is directly proportional to the radial distance from the rotor 14, such that the radial height and / or cross-sectional area of ​​the turns 62 of the coil 36 at the radial distance farthest from the rotor 14 is greater than the radial height and / or cross-sectional area of ​​the turns 62 of the coil 36 at the radial distance closest to the rotor 14.

[0059] Figure 7 An embodiment of coils 36 disposed in slots 34 of stator 12 is shown. Figure 7 A total of five turns 62a-62e are provided in the slot 34 in the embodiment of the present invention. For ease of description herein, each turn in the coil 36 is numbered one (1) starting from the distal end 54 of the slot 34, all the way to the last turn at the proximal end 56 of the slot 34. Thus, turn 62a corresponds to turn 1, turn 62b corresponds to turn 2, and so on. The embodiment of the slot 34 also includes a slot opening 66 formed by an extension 68 of the tooth 30. The slot opening 66 is smaller in size than the proximal end 56.

[0060] The cross-sectional shape of each of the turns 62a-62e may also take the form of a trapezoid, similar to the cross-sectional shape of the slot 34. In addition to the above discussion of the distal and proximal ends of the trapezoid being curved, the corners 70 of each of the turns 62a-62e may be rounded, chamfered, or other shapes other than the sharp vertices of the typical geometric trapezoidal shape. The rounded / chamfered / etc. shapes of the corners 70 may be the result of a manufacturing operation, such as 3D printing, casting, milling, or a post-printing / post-casting final milling operation, etc.

[0061] Each of the turns 62a-62e of the coil 36 is characterized by a turn height (h t )72, the turn height can be measured in the radial direction and is referred to as the radial height, and the entire coil 36 is characterized by the coil height (h c )74, the coil height can also be measured in the radial direction. Figure 7 As shown, the turn height 72 of each of the turns 62a-62e decreases as the turn progresses from the distal end 54 of the slot 34 to the proximal end 56 of the slot. The cross-sectional area of ​​each of the turns 62a-62e also decreases as the turn progresses from the distal end 54 of the slot 34 to the proximal end 56 of the slot 34. Figure 7 In the illustrated embodiment, each of the turns 62a-62e has a different radial height and a different cross-sectional area relative to adjacent turns of the turns 62a-62e. In addition, except for the turns of the coil located at the distal end 54 of the slot 34, each of the turns 62a-62e includes a reduced cross-sectional area and a reduced radial height relative to the turns 62a-62e located radially outside each of the turns 62a-62e.

[0062] Figure 7 It is also shown that the stator 12 can be segmented, wherein the segmented stator includes a first stator segment 84 and a second stator segment 86. In the illustrated embodiment, the first stator segment 84 and the second stator segment 86 are initially separate segments that are subsequently joined together to form the integrated stator 12. Providing a segmented stator in some embodiments allows the coil 36 to be installed in the slot 34, and the slot 34 is covered by a portion of the segmented stator to enclose the coil 36 in the slot 34. When the first stator segment 84 has an annular shape, the first stator segment 84 can be axially slid into place before coupling with the second stator segment 86. If the first stator segment itself is segmented, a component of the first stator segment 84 can be coupled to the second stator segment 86 if the arc length of the component is, for example, less than half of the circumferential extent of the stator 12. The first stator segment 84 and the second stator segment 86 can be fixed to the second stator segment 86, for example, by releasably coupling. In some embodiments, the first segment 84 may be releasably coupled to the second segment 86 using threaded fasteners, while in other embodiments, the first stator segment 84 and the second stator segment 86 may be permanently affixed, such as by metallurgical bonding. Figure 7 The stator 12 shown in FIG. 1 shows a first stator segment 84 in the form of a stator base 28, but in other embodiments, the stator can be segmented at other locations. For example, in one form, the stator 12 can be segmented in a radial direction. In a specific example, the slot 34 can be divided along a dividing line defined in the radial direction, thereby dividing the slot radially into two parts. Multiple slots 34 can be divided in this way, and when assembled into a whole, can form the annular shape of the stator 12.

[0063] In some forms, the turns 62a-62e may be electrically isolated from the ground insulation 40 to separate the turns 62a-62e from the stator 12, and turn insulation is provided between the turns 62a to separate each of the turns 62a-62e from each other. Figure 7 In the example of FIG. 1 , for convenience, the ground insulation 40 and the turn insulation 75 are depicted in separate single locations, but it should be understood that the ground insulation 40 and the turn insulation 75 may be in separate single locations. Figure 7 Similar ground insulation 40 and turn insulation 75 are found in similar locations elsewhere in the embodiment of FIG. In addition, the space between the turns of the double-layer turn configuration (see, for example, FIG. Figure 6 The space 64 in the coil 70 can be filled with ground insulation 40 or turn insulation 75. Due to the unexpected relationship found between turn height 72 and coil height 74, it was determined that ground insulation less than 20 mils and turn insulation less than 10 mils are useful in any given embodiment.

[0064] Now go to Figure 8 , the relationship of turn height to coil height of the present disclosure can be plotted as a function of the number of turns of the coil, and then the same relationship can also be plotted for the turns 62 of the prior art motor 10. Figure 8 The y-axis corresponds to the ratio and the x-axis corresponds to the number of any given turns 62. It can be immediately noted that the prior art motor 10 having turns 62 with constant height is a straight horizontal line 76 with zero slope. The prior art motor 10 having turns with constant area is a line 78 with a positive slope. Since the height of the turns 62 of the present disclosure decreases as the number of turns increases (see above), Figure 7 ), the motor 10 of the present disclosure presents a line 80 having a negative slope.

[0065] Fig. 9 The ratio r of the motor 10 is shown nt The motor exhibits improved performance and a greater relationship has been derived. It has been found that the relationship The motor 10 provides the desired operability and efficiency, where n is the number of turns. Several different arrangements of turns 62 have been evaluated and determined to provide the desired operability and efficiency. Lines 85 and 87 show the motor 10 according to the present disclosure, which satisfies the ratio of the number of all turns in the motor 10. This relationship is plotted in Fig. 9 The line 82 shows that there is a relationship that satisfies all turns of the machine 10. The motor 10 of turn 62 is located on the left side of line 82, and does not satisfy the relationship The motor 10 has one or more turns, which results in a ratio r nt Located to the right of line 82. Fig. 9Two prior art devices are plotted in FIG. 8 , represented by lines 88 and 90 , which include turns of constant height and which include violations of the ratio at higher turn counts for these devices. The number of turns of line 88 has at least a violation ratio The number of turns is 4, while line 90 has at least a violation ratio of turns 8, 9 and 10. Fig. 9 Two additional prior art devices are plotted in FIG. 8 , represented as lines 89 and 91 , which include turns with constant cross-sectional area and include violations of the ratio at higher turn counts for these devices. The number of turns of line 89 has at least a violation ratio The number of turns is 4, while line 90 has at least a violation ratio of turns 8, 9 and 10. Fig. 9 It is also apparent from the description of that the ratio of lines 85 and 87 of the motor 10 of the present disclosure decreases as the number of turns increases. Prior art devices of constant radial height have a flat or zero slope ratio as the number of turns increases. Prior art devices of constant cross-sectional area have an increasing ratio as the number of turns increases.

[0066] In combination with the discovery of the unexpected relationships discussed above, including the ratio r of the motor 10 exhibiting improved performance nt The relationship between the number of turns and the number of turns, and having derived the above greater relationship for this purpose, it has been found that further details of the configuration of the stator 12 and the coil 36 may also lead to improved performance. Although the above two embodiments use ten turns ( Figure 5 and Figure 6 ) and five turns ( Figure 7 ), but it has been found that improved performance can be achieved by using between 4-20 turns per coil. In some embodiments of the stator 12, all coils 36 will use the same number of turns.

[0067] In addition to the above, it is also contemplated that the motor 10 operates within the alternating current (A / C) frequency range, which also improves performance. The motor 10 of the embodiments disclosed herein is contemplated to operate between 200-2000 Hz.

[0068] In combination with the relationships discovered and discussed above, other aspects may also be used to improve the performance of the stator. Fig.10A stator 12 is shown having stator arc slots 92 defined by arc segments measured from the central longitudinal axis 16. The arc segments may be defined between lines that bisect the space between adjacent stator slots 34. The stator arc slots 92 include a single slot 34 for use with one or more coils 36 (e.g., a double-layer arrangement as shown above). The arc segments are defined by a slot angle 94, which may be used to determine the total number of slots 34 distributed circumferentially around the stator 12. It is contemplated that in any given embodiment of the stator 12, the slot angle 94 may vary within any range between 5-30 degrees, which may produce an electric machine 10 having between 12-72 stator arc slots 92.

[0069] Fig.11 A cross-sectional view of the stator 12 is depicted, showing other aspects that can be used to improve the performance of the stator in conjunction with the relationships discovered and discussed above. The coils 36 are shown as being wound around corresponding stator teeth 30 and in a double stack configuration within the slots 34. The coils 36 extend along the axial length of the teeth 30 before forming end turns that wrap the coils 36 around the ends of the teeth 30. The axial distance of the teeth 30 may be referred to as the stack length 96. The length of the end turns or end length 98 measures the length of the turn that arcs around the tooth 30. The ratio between the end length 98 and the stack length 96 (referred to as the end / stack length ratio) may also be used to further improve the performance of the motor. It is contemplated that the end / stack length ratio is between 0.25-1.0.

[0070] A table is provided herein that describes the ranges of various features discussed herein that, in some embodiments, result in further improved performance. It should be understood that not all embodiments include properties within one or more of the ranges provided below. Some embodiments of the motor 10 have any of the following: (1) each turn of the coil has a different cross-sectional area and a different radial height relative to adjacent turns of the coil; (2) each turn of the coil, except for the turns of the coil located at the distal ends of the stator slots, includes a reduced radial height relative to the turns of the coil located radially outside each turn of the coil; and / or (3) the relationship r discussed above is satisfied. nt The turns may include components and operations having properties with values ​​within any range specified in Table 1 below:

[0071]

[0072] Table 1

[0073] Fig.12An embodiment of a vehicle 100 having any form of an electric machine 10 disclosed herein, including variations of the stator 12 and coils 36, is shown, capable of exchanging electric power with one or more aspects of the vehicle 100. The vehicle 100 also includes a controller 102 for regulating the electric machine 10 and a power element 104 for exchanging electric power with the electric machine 10. In one form, the controller 102 includes power electronics, such as an electric drive, for regulating the operation of the controller 102. The vehicle 100 can take a variety of forms, including aircraft, automobiles, trucks, tractors, ships, and trains, as well as possible other forms. The power element 104 can be a drive shaft, a gas turbine engine shaft (e.g., a high pressure shaft, a low pressure shaft, etc.), etc., for receiving power from the electric machine 10 or delivering power to the electric machine 10. In a specific form, the electric machine 10 is integrated with a hybrid electric system for use with a gas turbine engine to power an aircraft, a land vehicle, or a watercraft.

[0074] Now go to Fig.13 , one or more portions of the controller 102 may be implemented using the computing device 106, Figure 5 One embodiment of a computing device 106 is shown. The computing device 106 may include one or more processors 106A and one or more memory devices 106B. The one or more processors 106A may include any suitable processing device, such as a microprocessor, a microcontroller, an integrated circuit, a logic device, and / or other suitable processing device. The one or more memory devices 106B may include one or more computer-readable media, including but not limited to non-transitory computer-readable media, RAM, ROM, hard disk drives, flash drives, and / or other memory devices.

[0075] One or more memory devices 106B may store information accessible by one or more processors 106A, including computer-readable instructions 106C executable by one or more processors 106A. Instructions 106C may be any set of instructions that, when executed by one or more processors 106A, cause one or more processors 106A to perform operations. In some embodiments, instructions 106C may be executed by one or more processors 106A to cause one or more processors 106A to perform operations, such as any operations and functions for which the controller and / or computing device 106 is configured, operations of any of the above systems (e.g., motor 10, etc.) as described herein, and / or any other operations or functions of one or more computing devices 106 (e.g., as a full authority digital engine controller). Instructions 106C may be software written in any suitable programming language, or may be implemented in hardware. Additionally, and / or alternatively, instructions 106C may be executed in logically and / or virtually independent threads on one or more processors 106A. One or more memory devices 106B may also store data 106D that may be accessed by one or more processors 106A. For example, data 106D may include data indicative of outside air conditions, power flow, data indicative of engine / vehicle operating conditions, and / or any other data and / or information described herein.

[0076] The computing device 106 may also include a network interface 106E for communicating with other components of the systems described herein (e.g., via a communication network). The network interface 106E may include any suitable components for interfacing with one or more networks, including, for example, transmitters, receivers, ports, controllers, antennas, and / or other suitable components. One or more devices may be configured to receive one or more commands from the computing device 106 or to provide one or more commands to the computing device 106.

[0077] Network interface 106E may include any suitable components for interfacing with one or more networks, including, for example, transmitters, receivers, ports, controllers, antennas, and / or other suitable components.

[0078] The technology discussed herein relates to computer-based systems and the actions taken by computer-based systems and the information sent to and from computer-based systems. Those of ordinary skill in the art will recognize that the inherent flexibility of computer-based systems allows for multiple possible configurations, combinations, and divisions of tasks and functions between and among components. For example, the processes discussed herein can be implemented using a single computing device or multiple computing devices working in combination. Databases, memories, instructions, and applications can be implemented on a single system or distributed on multiple systems. Distributed components can operate sequentially or in parallel.

[0079] Fig.14A A method 108a for building an electric machine is disclosed that includes providing at least a portion of a stator 12 having at least a portion of a stator slot 34 at step 109. The step of providing at least a portion of the stator 12 includes any of a variety of actions, including but not limited to procuring at least a portion of the stator 12, such as through a financial transaction to purchase at least a portion of the stator 12, or taking physical possession of at least a portion of the stator 12 procured by another person. In some forms, the act of providing at least a portion of the stator 12 refers to a physical act of placing at least a portion of the stator 12 on a work surface or within an enclosure, such as, but not limited to, a workbench or workstation. Furthermore, it should be understood that "at least a portion" of the stator 12 includes any complete stator 12 as well as any segmented stators of the various embodiments discussed herein, including Figures 17A-17D Similarly, "at least a portion" of stator slots 34 includes any stator segment (e.g., Figures 17A-17B 108a). Step 110 includes positioning at least a portion of the stator 12 having at least a portion of the stator slot 34 relative to the coil 36, the coil 36 including a plurality of turns 62 stacked on each other in a radial direction between the proximal and distal ends of the stator slot 34, each turn 62 of the coil 36 having a different cross-sectional area and a different radial height relative to the adjacent turns 62 of the coil 36. In one form, the stator is a segmented stator, which may include a first stator segment 84 and a second stator segment 86. The method 108a may also include the step of winding the coil 36 directly around the tooth 30. For example, the coil may include turns 62 that already have a cross-sectional shape suitable for the intended radial position within the slot 34. In another form, the coil 36 having turns 62 formed according to the embodiments disclosed herein may be formed and then assembled to the teeth 30 of the stator segment before the stator segment is coupled to another stator segment. The coil 36 assembled with turns 62 before coupling to another stator segment may be referred to as an intermediate segment with a coil. Multiple intermediate segments with coils may be assembled before being joined together to form a complete stator 12. The intermediate segments may also be used with other methods disclosed herein.

[0080] Fig. 14BA method 108b for building an electric machine is disclosed that includes providing at least a portion of a stator 12 having at least a portion of a stator slot 34 at step 109. The step of providing at least a portion of the stator 12 includes any of a variety of actions, including but not limited to procuring at least a portion of the stator 12, such as through a financial transaction to purchase at least a portion of the stator 12, or taking physical possession of at least a portion of the stator 12 procured by another person. In some forms, the act of providing at least a portion of the stator 12 refers to a physical act of placing at least a portion of the stator 12 on a work surface or within a housing (such as, but not limited to, a workbench or workstation). Furthermore, it should be understood that "at least a portion" of the stator 12 includes any complete stator 12 as well as any segmented stators of the various embodiments discussed herein, including Figures 17A-17D Similarly, "at least a portion" of stator slots 34 includes any stator segment (e.g., Figures 17A-17B 1 and 1 ). Step 110 includes positioning at least a portion of the stator 12 having at least a portion of the stator slots 34 relative to the coil 36, the coil 36 including a plurality of turns 62 stacked on top of each other in a radial direction between a proximal end and a distal end of the stator slots 34, each turn 62 of the coil 36 having a different cross-sectional area and a different radial height relative to an adjacent turn 62 of the coil 36. In one form, the stator is a segmented stator, which may include a first stator segment 84 and a second stator segment 86. Step 112 includes inserting the coil 36 into at least a portion of the stator slots 34. Inserting the coil 36 into the slots 34 may be in a radial direction, for example if the segmented stator is Figure 7 , where the first stator segment 84 is located radially outside the second stator segment 86, it is contemplated. Other embodiments of the segmented stator may include inserting the coil 36 into the slot 34 in the circumferential direction, for example if the stator 12 includes a segment split in the radial direction (e.g., the slot is cut into two parts in the radial direction). At step 114, the method 108b includes at least a portion of the stator being a first stator segment, and also includes engaging the first stator segment 84 with the second stator segment 86. The engaging step may include moving the stator segment 84 in the axial direction and / or radial direction to couple with the second stator segment 86. For example, if the stator segment 84 is a tooth 30, the ring may be inserted in the axial direction and / or radial direction to engage with the annular yoke. However, if the stator segment 84 includes multiple segments that together form an annular ring, the individual segments may be coupled if they have a sufficiently small arc length (e.g., less than half of the circumferential extent of the stator segment 86).

[0081] The method 108b may additionally include using additive manufacturing to construct the coil 36, or using casting and molten metal to manufacture the coil. In some forms, the method 108b also includes machining the coil as part of the manufacturing process to roughly cut the coil from stock material, and / or as a final form. The method 108b may also include securing the second stator segment to the first stator segment.

[0082] Now turn to Fig.15 As mentioned above, the arrangement shown can be referred to as a single-layer winding, where the turns 62a-62e are from a single coil 36. Any of the above-described embodiments of the stator 12, stator slots 34, and turns 62 are applicable to Fig.15 The embodiments shown in . Only a few non-limiting examples are described, Fig.15 The embodiment shown in may include turns 62 having a relationship between the radial height of the turn 62 and its position between the proximal end 56 and the distal end 54, or alternatively, a relationship between the radial height and the distance of the turn 62 from the rotor 14. Ground insulation 40 and / or turn insulation 75 may also be included. The or shown in Table 1 Figure 8 and Fig. 9 The relative values ​​stated in any relationship shown in Fig.15 The embodiment shown in .

[0083] As mentioned above, Fig.16 The arrangement shown in can be referred to as an upper and lower double-layer overlapping winding, in which the turns 62a-62c from one coil 36a are stacked on top of the turns 62d-62f from the other coil 36b and overlap radially. Fig.15 As described above, any of the above embodiments of the stator 12, stator slots 34 and turns 62 are applicable to Fig.16 The embodiments shown in . Just to illustrate a few non-limiting examples, ground insulation 40 and / or turn insulation 75 may also be included. The or Figure 8 and Fig. 9 The relative values ​​stated in any relationship shown in Fig.16 The embodiment shown in .

[0084] In particular, for Fig.16, the turns 62 distributed throughout the slot 34 include the above-described relationship between the radial height and / or cross-sectional area of ​​the turns 62 and their position between the proximal end 56 and the distal end 54, or, alternatively, the relationship between the radial height and / or cross-sectional area and the distance of the turns 62 from the rotor 14. For example, the turns 62 located near the distal end 54 have a greater radial height than the turns 62 located near the proximal end 56. In some forms, the turns 62 located near the distal end 54 also have a greater cross-sectional area than the turns 62 located near the proximal end 56. This relationship between the radial height and / or cross-sectional area of ​​any given turn 62 relative to its radial position within the slot 34 may also apply regardless of whether the turn 62 is included in the first coil 36a or the second coil 36b. For example, turn 62e of coil 36a positioned closest to proximal end 56 may have a greater radial height and / or a greater cross-sectional area than turn 62c of coil 36b, which is positioned closest to distal end 54 of slot 34 relative to other turns 62 in coil 36b.

[0085] and Figure 7 The segmented stator shown in is similar to that shown in Figures 17A-17D Various embodiments of a first stator segment 84 are shown that may be coupled to a second stator segment (not shown) to form a partial or complete stator 12 . Fig.17A A circumferential segment having a single tooth is shown, wherein the segment may be attached to adjacent stator segments 86 to form an annular stator. Fig. 17B Teeth 30 are shown which can be inserted radially and / or axially into the annular yoke. Fig. 17C An inserted pole shoe associated with the tooth 30 is shown. Fig.17D A circumferential segment is shown with a plurality of teeth 30 which can be fixed to a similar circumferential segment.

[0086] Fig.18 A stator 12 is shown, which is placed on a rotor 14 ( Fig.18 56), which is not shown in the figure, but is located at the top of the figure, closest to the radial inner side of the proximal end 56), which can be used Figure 1 B. Turns 62a-62e are arranged to provide a relationship of the radial height of each turn 62 relative to the position of the turn 62 between the proximal end 56 and the distal end 54. The turn 62 closest to the rotor 14, near the proximal end 56, has a smaller radial height and / or a smaller cross-sectional area than the turn 62 located radially farthest from the rotor 14. In some embodiments, the relationship between the turns 62 located near the proximal end 56 and having a smaller radial height and / or a smaller cross-sectional area than the turns 62 located near the distal end 54 can apply to all turns 62. For example, in Fig.18In the illustrated embodiment, any turn 62 that is positioned radially inward relative to another turn 62 will have a smaller radial height and / or a smaller cross-sectional area. Conversely, any turn 62 that is positioned radially outward relative to another turn 62 will have a larger radial height and / or a larger cross-sectional area. In this sense, the radial height and / or cross-sectional area of ​​each turn 62 of the coil 36 is directly proportional to the radial distance from the rotor 14, such that the turns 62 of the coil at the farthest radial distance from the rotor 14 have a radial height and / or cross-sectional area that is greater than the radial height and / or cross-sectional area of ​​the turns 62 of the coil 36 at the closest radial distance to the rotor 14.

[0087] Regarding the above Fig.15 and Fig.16 As described above, any of the above embodiments of the stator 12, stator slots 34 and turns 62 are applicable to Fig.18 The embodiments shown in . Just to illustrate a few non-limiting examples, ground insulation 40 and / or turn insulation 75 may also be included. The or Figure 8 and Fig. 9 The relative values ​​described in any relationship shown in also apply to the embodiment shown in FIG. 17 .

[0088] In some embodiments, the coil 36 may include any of the variations of the turns 62 described above. In further embodiments, multiple turns 62 of the coil 36 may have the variations described above, wherein additional turns 62 in electrical communication with the multiple turns 62 have different profiles. In this context, the coil 36 includes not only multiple turns 62 having any of the variations described above, but also additional turns 62 having different geometries. Figure 7 , the coil 36 may include turns 62a, 62b, and 62c of the turns 62 having any of the variations disclosed herein, and the additional turns 62 may include turns 62d and 62e. For example, the plurality of turns 62 may include any of the variations described above, wherein the additional turns have a constant cross-sectional area. Yet another example includes additional turns having a constant cross-sectional area but different radial heights. Other variations are also contemplated.

[0089] The technical advantage of the motor 10 is that it transmits electromechanical power more efficiently. The coil 36 can reduce ohmic losses relative to prior art motors in a range of different configurations and operating conditions. In general, ohmic losses may depend on the current density in the winding, where ohmic losses are generally the highest volumetric heat source for the motor. Compared to the solid conductors of the present disclosure, Litz wire windings have a low slot filling factor (related to DC losses), which limits the electrical load of the machine due to the current density in the wire strands. On the other hand, solid conductors formed into a slot geometry have a high slot filling factor, but are more susceptible to eddy currents, which affect the current density distribution at high frequencies (related to AC losses). Any one or more of the parameters provided in Table 1 provide a motor with better performance and higher efficiency than those motors made of Litz wire and operated with the same parameters.

[0090] Further aspects are provided by the subject matter of the following clauses:

[0091] A motor comprises: a stator slot having a distal end and a proximal end arranged in a radial direction, wherein the distal end is oriented to be radially opposite to the proximal end; and a coil disposed in the stator slot, the coil having a plurality of turns, the plurality of turns being stacked on each other in a radial direction between the proximal end and the distal end of the stator slot, each turn of the coil having a different cross-sectional area and a different radial height relative to an adjacent turn of the coil.

[0092] An electric machine according to the preceding clause, wherein, except for the turns of the coil located at the distal ends of the stator slots, each turn of the coil comprises a reduced cross-sectional area and a reduced radial height relative to the turns of the coil located radially outside each turn of the plurality of turns of the coil.

[0093] An electric machine as claimed in any preceding clause, wherein the stator slots comprise a trapezoidal cross-sectional shape.

[0094] An electric machine as claimed in any preceding clause, wherein, for each turn of the plurality of turns, In the equation, r nt is the limiting ratio, h t is the coil n th Height of turns, h c is the height of the coil, and n is the coil number being evaluated.

[0095] An electric machine as claimed in any preceding clause, wherein the coil comprises at least 4 turns and no more than 20 turns.

[0096] An electric machine as claimed in any preceding clause, wherein the operating frequency of the coils is between 200 Hz - 2000 Hz.

[0097] The electric machine according to any of the preceding clauses, further comprising a stator having the stator slots, wherein the stator comprises a plurality of stator slots having corresponding stator slot angles, wherein the stator slots are located within stator arc slots of the plurality of stator slots, wherein each stator arc slot comprises a stator slot angle, and wherein the stator slot angle is between 5-30 degrees.

[0098] An electric machine as described in any of the preceding clauses, wherein each turn of the plurality of turns has an end length / stack length ratio between 0.25-1, wherein the end length is the arc length of a given end turn of the plurality of turns, and wherein the stack length is the length between opposing end turns of the plurality of turns.

[0099] An electric machine as claimed in any one of the preceding clauses, wherein the coil comprises an electrically conductive material, and wherein the electrical conductivity of the electrically conductive material is between 0.3-1 pu International Annealed Copper Standard (IACS) copper at room temperature.

[0100] An electric machine as in any of the preceding clauses, wherein ground insulation between the coil and the stator slots has a thickness of less than 20 mils, and wherein insulation between turns of the plurality of turns has a thickness of less than 10 mils.

[0101] An electric machine as claimed in any one of the preceding clauses, wherein the coil comprises a further plurality of turns in electrical communication with the plurality of turns and stacked, each turn of the further plurality of turns having a constant cross-sectional area.

[0102] An electric machine as claimed in the preceding clause, wherein the stator slots are located in a stator, and wherein the stator is a segmented stator.

[0103] An electrical machine as claimed in any preceding clause, further comprising a rotor electromagnetically coupled to the stator during operation of the electrical machine.

[0104] An electric machine as claimed in any preceding clause, wherein the plurality of turns are in the form of concentrated windings.

[0105] An electric machine as claimed in any preceding clause, wherein the plurality of turns are in the form of a distributed winding.

[0106] An electric machine as claimed in any preceding clause, wherein the proximal end comprises a slot opening.

[0107] An electric machine as claimed in any preceding clause, wherein each winding of the plurality of windings is trapezoidal in shape.

[0108] An electric machine as claimed in any preceding clause, wherein the plurality of windings in the stator slots comprises single layer windings.

[0109] An electric machine as claimed in any of the preceding clauses, wherein the plurality of windings in the stator slots comprises double layer windings.

[0110] An electric machine as claimed in any one of the preceding clauses, wherein the stator slots comprise a trapezoidal cross-sectional shape having distal and proximal ends and opposing side walls inclined towards each other at a taper angle.

[0111] An electric machine as claimed in any preceding clause, wherein each winding of the plurality of windings is a solid winding.

[0112] An electric machine as claimed in any preceding clause, wherein each turn is a solid conductor.

[0113] An electric machine as claimed in any preceding clause, wherein the distributed winding comprises a hairpin winding.

[0114] A motor comprises: a rotor configured to rotate about a central longitudinal axis; a stator radially offset from the rotor and electromagnetically coupled to the rotor, the stator having: a stator slot having a trapezoidal cross-sectional shape, the trapezoidal cross-sectional shape having a distal end and a proximal end and opposing side walls, the opposing side walls being inclined toward each other as the opposing side walls extend between the distal end and the proximal end, the distal end of the trapezoidal cross-sectional shape being larger than the proximal end; and a coil having a plurality of turns arranged in the stator slots in a radial direction, the radial height of each turn of the coil being proportional to the radial distance from the rotor, such that the radial height of the turn of the coil at the farthest radial distance from the rotor is greater than the radial height of the turn of the coil at the closest radial distance from the rotor.

[0115] An electric machine according to the preceding clause, wherein the stator is a segmented stator.

[0116] An electric machine as described in the preceding clause, wherein the plurality of turns is in the form of a single layer winding.

[0117] An electric machine as claimed in any preceding clause, wherein the plurality of turns are in the form of concentrated windings.

[0118] An electric machine as claimed in any preceding clause, wherein the plurality of turns are in the form of a distributed winding.

[0119] An electric machine as claimed in any preceding clause, wherein the stator slots comprise a trapezoidal cross-sectional shape.

[0120] An electric machine as claimed in any preceding clause, wherein, for each turn of the plurality of turns, In the equation, r nt is the limiting ratio, h t is the coil n th Height of turns, h c is the height of the coil, and n is the coil number being evaluated.

[0121] An electric machine as claimed in any preceding clause, wherein the coil comprises at least 4 turns and no more than 20 turns.

[0122] An electric machine as claimed in any preceding clause, wherein the operating frequency of the coils is between 200 Hz - 2000 Hz.

[0123] The electric machine according to any of the preceding clauses, further comprising a stator having the stator slots, wherein the stator comprises a plurality of stator slots having corresponding stator slot angles, wherein the stator slots are located within stator arc slots of the plurality of stator slots, wherein each stator arc slot comprises a stator slot angle, and wherein the stator slot angle is between 5-30 degrees.

[0124] An electric machine as described in any of the preceding clauses, wherein each turn of the plurality of turns has an end length / stack length ratio between 0.25-1, wherein the end length is the arc length of a given end turn of the plurality of turns, and wherein the stack length is the length between opposing end turns of the plurality of turns.

[0125] An electric machine as claimed in any one of the preceding clauses, wherein the coil comprises an electrically conductive material, and wherein the electrical conductivity of the electrically conductive material is between 0.3-1 pu of International Annealed Copper Standard copper at room temperature.

[0126] An electric machine as in any of the preceding clauses, wherein ground insulation between the coil and the stator slots has a thickness of less than 20 mils, and wherein insulation between turns of the plurality of turns has a thickness of less than 10 mils.

[0127] An electric machine as claimed in any preceding clause, wherein the proximal end comprises a slot opening.

[0128] An electric machine as claimed in any preceding clause, wherein each winding of the plurality of windings is trapezoidal in shape.

[0129] An electric machine as claimed in any preceding clause, wherein the plurality of windings in the stator slots comprises single layer windings.

[0130] An electric machine as claimed in any of the preceding clauses, wherein the plurality of windings in the stator slots comprises double layer windings.

[0131] An electric machine as claimed in any one of the preceding clauses, wherein the stator slot comprises a trapezoidal cross-sectional shape having distal and proximal ends and opposing side walls inclined towards each other at a taper angle.

[0132] An electric machine as claimed in any preceding clause, wherein each winding of the plurality of windings is a solid winding.

[0133] An electric machine as claimed in any preceding clause, wherein each turn is a solid conductor.

[0134] An electric machine as claimed in any preceding clause, wherein the distributed winding comprises a hairpin winding.

[0135] A method of constructing an electric machine, comprising: providing at least a portion of a stator having at least a portion of a stator slot; and positioning the at least a portion of the stator having the at least a portion of the stator slot relative to a coil, the coil comprising a plurality of turns stacked on each other in a radial direction between a proximal end and a distal end of the stator slot, each turn of the coil having a different cross-sectional area and a different radial height relative to an adjacent turn of the coil.

[0136] The method of the preceding clause, further comprising inserting the coil into the at least a portion of the stator slots.

[0137] A method according to any of the preceding clauses, wherein the at least a portion of the stator slots is a first stator segment, and the method further comprises joining the first stator segment with a second stator segment.

[0138] The method of any of the preceding clauses, further comprising at least one of constructing the coil using additive manufacturing, manufacturing the coil using casting and molten metal, or machining the coil.

[0139] A method as claimed in any of the preceding clauses, further comprising securing the second stator segment to the first stator segment.

[0140] A method of building an electric machine includes: positioning a first stator segment having stator slots relative to a coil, the coil including a plurality of turns stacked on each other in a radial direction between a proximal end and a distal end of the stator slots, each turn of the coil having a different cross-sectional area and a different radial height relative to an adjacent turn of the coil; inserting the coil into the stator slots; and joining the first stator segment to a second stator segment.

[0141] An electric machine comprises: a rotor configured to rotate about a central longitudinal axis; a stator radially offset from the rotor and electromagnetically coupled to the rotor, the stator having stator slots; and a coil having a device for reducing ohmic losses.

[0142] An electric machine according to the preceding clause, wherein the means for reducing ohmic losses comprises a solid conductor having a shaped profile configured to reduce ohmic losses.

[0143] An electric machine as claimed in any preceding clause, wherein the means for reducing ohmic losses comprises a solid conductor having a shaped profile configured to reduce ohmic losses.

[0144] This written description uses examples to disclose the present disclosure, including the best mode, and also to enable any person skilled in the art to practice the present disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the present disclosure is defined by the claims, and may include other examples that occur to one skilled in the art. Such other examples are intended to fall within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims.

Claims

1. A motor, characterized in that: include: a stator slot having a distal end and a proximal end arranged in a radial direction, wherein the distal end is positioned radially opposite to the proximal end; as well as A coil is disposed in the stator slot, the coil having a plurality of turns, the plurality of turns being stacked on each other in a radial direction between the proximal end and the distal end of the stator slot, each turn of the coil having a different cross-sectional area and a different radial height relative to an adjacent turn of the coil.

2. The motor according to claim 1, characterized in that in, Each turn of the coil, except for turns of the coil located at the distal ends of the stator slots, includes a reduced cross-sectional area and a reduced radial height relative to turns of the coil located radially outward of each turn of the plurality of turns of the coil.

3. The motor according to claim 1, characterized in that in, The stator slots include a trapezoidal cross-sectional shape.

4. The motor according to claim 1, characterized in that in, For each turn in the plurality of turns, Among them, r nt is the limiting ratio, h t is the coil n th Height of turns, h c is the height of the coil, and n is the coil number being evaluated.

5. The motor according to claim 1, characterized in that in, The coil comprises at least 4 turns and no more than 20 turns.

6. The motor according to claim 1, characterized in that in, The operating frequency of the coil is between 200 Hz and 2000 Hz.

7. The motor according to claim 1, characterized in that Further comprising a stator having the stator slots, wherein the stator comprises a plurality of stator slots having corresponding stator slot angles, wherein the stator slots are located within stator arc slots of the plurality of stator slots, wherein each stator arc slot comprises a stator slot angle, and wherein the stator slot angle is between 5-30 degrees.

8. The motor according to claim 1, characterized in that in, Each turn of the plurality of turns has an end length / stack length ratio between 0.25-1, wherein the end length is the arc length of a given end turn of the plurality of turns, and wherein the stack length is the length between opposite end turns of the plurality of turns.

9. The motor according to claim 1, characterized in that in, The coil comprises a conductive material, and wherein the conductive material has a conductivity between 0.3-1 pu of International Annealed Copper Standard (IACS) copper at room temperature.

10. The motor according to claim 1, characterized in that in, The ground insulation between the coil and the stator slot has a thickness of less than 20 mils, and wherein insulation between turns of the plurality of turns has a thickness of less than 10 mils.

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